#include <bits/stdc++.h>
using namespace std;
int main()
{
ios_base::sync_with_stdio(0);
cin.tie(0); cout.tie(0);
int n, m, s;
cin >> n >> m >> s;
vector<long long> a(n), b(n);
for (int i = 0; i < n; i++)
cin >> a[i] >> b[i];
vector<int> vt(n);
for (int i = 0; i < n; i++)
vt[i] = i;
sort(vt.begin(), vt.end(), [&](int i, int j)
{
return (a[i] - b[i]) > (a[j] - b[j]);
});
vector<long long> pre(n + 1, LLONG_MIN);
vector<long long> suf(n + 2, LLONG_MIN);
if (m == 0)
{
for (int i = 0; i <= n; i++)
pre[i] = 0;
}
else
{
priority_queue<long long, vector<long long>, greater<long long>> pq;
long long sum = 0;
for (int i = 1; i <= n; i++)
{
int id = vt[i - 1];
pq.push(a[id]);
sum += a[id];
if (pq.size() > m)
{
sum -= pq.top();
pq.pop();
}
if (pq.size() == m)
pre[i] = sum;
else
pre[i] = LLONG_MIN;
}
}
if (s == 0 )
{
for (int i = 1; i <= n + 1; i++ )
suf[i] = 0;
}
else
{
priority_queue<long long, vector<long long>, greater<long long>> pq;
long long sum = 0;
for (int i = n; i >= 1; i--)
{
int id = vt[i - 1];
pq.push(b[id]);
sum += b[id];
if (pq.size() > s)
{
sum -= pq.top();
pq.pop();
}
if (pq.size() == s)
suf[i] = sum;
else
suf[i] = LLONG_MIN;
}
}
long long ans = 0;
bool check = false;
for (int i = 0; i <= n; i++ )
{
if (pre[i] > LLONG_MIN / 2 && suf[i + 1] > LLONG_MIN / 2 )
{
long long val = pre[i] + suf[i + 1];
if (!check || val > ans )
{
ans = val;
check = true;
}
}
}
cout << ans;
return 0;
}
